VENICE, JUNE 9 -- Secretary of State George P. Shultz today delivered an impassioned defense of Assistant Secretary Elliott Abrams, saying "he's done well" despite what Shultz called the "mistake" of misleading Congress about his solicitation of aid from Brunei for the Nicaraguan rebels.

Shultz was walking off the podium after a news conference here when he was asked about Abrams, the administration's chief spokesman for aid to the rebels, called contras. Shultz marched back to the microphone to declare that Abrams is "now doing an extraordinarily difficult job with great energy, with great skill and with great dedication."

Shultz said the administration supports Abrams "top to bottom." The secretary's strong backing for Abrams has angered some White House officials who believe Abrams has become an impediment to further congressional support for the contras. However, the officials say they have acceded to Shultz on the matter for the time being.

Abrams was criticized by members of Congress last week for making misleading statements about the U.S. role in the secret resupply mission for the contras. Some members said his credibility was so damaged he could no longer serve as an effective administration spokesman.

After a cargo plane carrying military equipment was shot down over Nicaragua last Oct. 5, Abrams and Shultz repeatedly denied that the U.S. government had any role in the resupply operation. Testimony in the Iran-contra hearings has shown that the resupply missions were being coordinated out of the White House by then-National Security Council aide Lt. Col. Oliver L. North Jr. Abrams has said North deceived him about the scope of the operation.

Shultz did not refer to these statements in his comments today. Instead, he said Abrams "made a mistake" by failing to disclose in testimony last Nov. 25 to the Senate Select Committee on Intelligence his solicitation of $10 million from the sultan of Brunei for the contras.

In testimony last Tuesday before the Iran-contra committee, Abrams said he had made a "great mistake" by not informing the Senate panel of the Brunei solicitation. He said he was "caught in a bind" because he did not have Shultz's authorization to tell the panel of the solicition.

House chief counsel John W. Nields Jr. suggested, however, that the reason for Abrams' misleading remarks was that he did not want to lead the Senate panel to the secret Swiss bank account where money from the U.S. arms sales to Iran was channeled in 1986.

Today, Shultz said Abrams "very quickly realized afterwards that he should have" informed Congress. "And he went back and corrected that mistake long before these hearings took place," Shultz said, referring to the Iran-contra hearings in Congress.

"So I think that that mistake doesn't change the quality of the work that he's done," Shultz said. "It doesn't change the importance -- at least as I judge it and he judges it and the president judges it, as a majority of the House and Senate judged it last year when they voted {in favor of aid to the contras}."

Shultz said Abrams has "dedicated himself" to fighting the Sandinista government in Nicaragua.